liminfoXLSX to JSON
Free web tool: XLSX to JSON
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Choose fileExcel 파일 (.xlsx, .xls), 최대 50MB
About XLSX to JSON
The XLSX to JSON Converter is a free, browser-based tool that reads Microsoft Excel files (XLSX and XLS formats) and outputs their row data as structured JSON arrays. The conversion uses the SheetJS (xlsx) library, which parses the entire workbook client-side. Each worksheet is converted independently using sheet_to_json, preserving column headers as JSON keys and each row as an object in the output array.
This tool is widely used by data engineers, frontend developers, and analysts who need to bridge Excel data into JavaScript applications, REST APIs, or data pipelines. Common use cases include migrating product catalogs, importing test fixtures, converting configuration tables, and preparing datasets for charting libraries. Files up to 50MB are supported, covering spreadsheets with tens of thousands of rows.
When a workbook contains multiple sheets, the tool detects all sheet names and presents a dropdown selector. Each sheet can be previewed independently, and the JSON output is displayed in a read-only monospace textarea. You can copy the result to the clipboard or download it as a .json file named after the original workbook and the selected sheet — for example, data_Sheet1.json.
Key Features
- Converts XLSX and XLS files to JSON arrays entirely in the browser using SheetJS
- Supports files up to 50MB with drag-and-drop or file picker upload
- Multi-sheet workbooks: all sheets are parsed and selectable via dropdown
- Column headers from row 1 are automatically mapped as JSON object keys
- Each worksheet row becomes a JSON object — empty cells are omitted by default
- One-click clipboard copy or .json file download per selected sheet
- Output filename is derived from the workbook name and sheet name automatically
- Clear status indicators for loading, success, and error states during conversion
Frequently Asked Questions
What Excel formats are supported?
The tool supports both .xlsx (Office Open XML) and .xls (legacy binary format) files. Both formats are parsed by the SheetJS library running entirely in your browser.
Does my spreadsheet get sent to a server?
No. The file is read using the browser File API and processed entirely by SheetJS running in your browser. Nothing is uploaded — your spreadsheet data stays on your device.
How are column headers handled in the JSON output?
SheetJS reads the first row of each sheet as column headers and uses those values as keys in the output JSON objects. If the first row contains blank cells, those columns may be omitted or given numeric keys.
What happens with a workbook that has multiple sheets?
All sheets in the workbook are parsed at once. A dropdown appears letting you select which sheet to view. The JSON output updates instantly when you switch sheets, and you can download each sheet separately.
Are merged cells or formulas preserved in the JSON output?
Formulas are evaluated to their cached values (the last calculated result stored in the file). Merged cells are typically represented by their top-left cell value; other cells in the merged range may appear empty in the JSON.
Can I convert large files with thousands of rows?
Yes. Files up to 50MB are supported. SheetJS is optimized for performance and can handle spreadsheets with tens of thousands of rows. Very large files may take a few seconds to parse depending on your device.
What does the JSON output look like?
Each sheet produces a JSON array of objects. For example, a sheet with columns Name and Age would produce [{"Name":"Alice","Age":30},{"Name":"Bob","Age":25}]. The output is pretty-printed with 2-space indentation.
How do I download the JSON result?
After conversion, click the Download button. The file is saved as a .json file named {workbook}_{sheet}.json, for example report_Sheet1.json. You can also use the Copy button to copy the JSON text directly to your clipboard.